4" Cat & DPF Race Pipe With Muffler | 2011-2015 GM 2500/3500 6.6L DURAMAX- 431029 FLEECE PERFORMANCE " Designed for both style and

Designed for both style and comfort

4" Cat Pipe

590 CFM Rating @ 7" H2O

It is the largest sizing that we make but we can make more or less fuel delivery within this largest group

4" Cat & DPF Race Pipe With Muffler | 2011-2015 GM 2500/3500 6.6L DURAMAX- 431029 FLEECE PERFORMANCE " Designed for both style andConstructed out of 16 gauge aluminized steel or T409 Stainless, this exhaust system is designed to simplify installation with included clamps, preweld contour bends and improved flanges. Enjoy a noticeable boost in performance, lowered EGTs and amplified air flow with this Mel's system. For powerhouse performance, Mel's delivers horsepower you can hear! Features: Ease of installation Contour Bent Hangers TorcTite Clamps No Bungs Fits Cab Box